Wireless communication device for controlling a target transmission power of a target cell using a classification of an overall channel quality in a cell cluster

ABSTRACT

A wireless communication device, a wireless communication method and a wireless communication system. The wireless communication device includes: a classification unit, used for, based on the channel qualities of downlinks of a target cell and other cells in a cell cluster on a specific resource block, classifying the overall condition of the channel quality; and a control unit, used for controlling, so as to determine the target transmitting power of the target cell on the specific resource block by using a power distribution method adapting to the classification. According to the scheme, the system throughput of a wireless network on the specific resource block under dense cell distribution can be maximized.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/122,557, filed Aug. 30, 2016, which is based on PCT filingPCT/CN2015/073702, filed Mar. 5, 2015, and claims priority to CN201410123043.9, filed Mar. 28, 2014, the entire contents of each areincorporated herein by reference.

FIELD

The disclosure generally relates to the technical field of wirelesscommunication, and in particular to a wireless communication device, awireless communication method and a wireless communication system, whichcan perform an efficient power control between cells.

BACKGROUND

In order to further solve the problem of data service requirement of awireless cellular network, 3GPP (The 3rd Generation Partnership Project)proposed, in the latest LTE-A evolution version Release 12, a solutionfor denser small cell deployment. By deploying small cells, a systemthroughput can be improved, a more effective coverage can also beprovided, so as to realize a load balancing. In a whole LTE-A network,the small cells are mainly deployed in the following three scenarios:deployed with a frequency same as a macro base station, deployed with afrequency different from a macro base station, or deployed without amacro base station. In a scenario of being deployed in the frequencydifferent from the macro base station, the small cell operates with afrequency different from the macro base station, and thus cross-layerinterference between the macro base station and the small cell may beignored, which is consistent with the research method for the scenarioof deployment without a macro base station. Therefore, from aperspective of network interference analysis, the small cell deploymentmay be classified into two types: a same-frequency deployment with onlycross-layer interference between the small cell and the macro basestation, and a different-frequency deployment with only same-layerinterference. And the different-frequency deployment of the small cellis a hotspot in 3GPP research.

Although a dense small cell deployment can greatly improve the spectrumefficiency of a network, it may bring serious same-layer interference,and increase the operation cost. In another aspect, interference of asmall cell network, especially interference in a dense deployment, is abottleneck of a further improvement of system performance. Therefore,interference management and energy efficiency are currently researchfocuses of a small cell project group of 3GPP. In a case of thedifferent-frequency deployment, that is, in a case that the cross-layerinterference between the macro base station and the small cell is nottaken into account, the dense deployment of small cells may make a userequipment be interfered by many other small cells at the same time.Therefore, the same-layer interference is a main constraint on systemperformance improvement.

SUMMARY

A wireless communication device is provided according to an aspect ofthe present disclosure. The wireless communication device includes: aclassification unit, configured to classify, based on channel qualitiesof downlinks of a target cell and other cells in a cell cluster on aspecific resource block, an overall channel quality; and a control unit,configured to perform a control to determine a target transmission powerof the target cell on the specific resource block by a power allocatingmethod adaptive to a classification of the overall channel quality.

A wireless communication method is provided according to another aspectof the present disclosure. The wireless communication method includes:classifying, based on channel qualities of downlinks of a target celland other cells in a cell cluster on a specific resource block, anoverall channel quality; and performing a control to determine a targettransmission power of the target cell on the specific resource block bya power allocating method adaptive to a classification of the overallchannel quality.

A wireless communication device is provided according to another aspectof the present disclosure. The wireless communication device includes: aclassification unit, configured to classify a user equipment in a cellcluster based on average channel quality of downlinks to the userequipment in a predetermined time period; an allocating unit, configuredto allocate a resource block set to the user equipment at least partlybased on a classification of the user equipment, wherein the allocatingunit allocates a same resource block set to user equipments of the sameclassification; and a control unit, configured to perform a control todetermine a target transmission power of a target cell on a specificresource block by a power allocating method adaptive to a classificationof the user equipment scheduled by the target cell on the specificresource block.

A wireless communication method is provided according to another aspectof the present disclosure. The wireless communication method includes:classifying a user equipment in a cell cluster based on average channelquality of downlinks to the user equipment in a predetermined timeperiod; allocating a resource block set to the user equipment at leastpartly based on a classification of the user equipment, wherein theallocating unit allocates a same resource block set to user equipmentsof the same classification; and performing a control to determine atarget transmission power of a target cell on a specific resource blockby a power allocating method adaptive to a classification of the userequipment scheduled by the target cell on the specific resource block.

A wireless communication system is further provided according to antheraspect of the present disclosure. The wireless communication systemincludes the wireless communication device according to the presentdisclosure.

With the wireless communication device and the wireless communicationmethod according to the present disclosure, a system throughput of awireless network on a specific resource block in a dense small celldeployment can be maximized.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objectives, features and advantages will be moreeasily understood with reference to the following descriptions ofembodiments of the present disclosure in conjunction with the drawings.In the drawings, same or corresponding reference numerals indicate sameor corresponding technical features or parts. In the drawings, sizes andrelative positions of units may not be drawn to scale.

FIG. 1 is a block diagram illustrating a functional configuration of awireless communication device according to an embodiment of the presentdisclosure;

FIG. 2 is a flowchart illustrating a process of a wireless communicationmethod according to an embodiment of the present disclosure;

FIG. 3 is a block diagram illustrating a functional configuration of awireless communication device according to an embodiment of the presentdisclosure;

FIG. 4 is a schematic diagram illustrating a variation characteristicthat a total throughput of a network varies with a transmission power ofa target cell in a case that an overall channel quality is good;

FIG. 5 is a sequence diagram illustrating a data transfer between a userequipment and a cell base station in a case that a wirelesscommunication device according to an embodiment of the presentdisclosure is integrated into the cell base station;

FIG. 6 is a block diagram illustrating a functional configuration of awireless communication device according to an embodiment of the presentdisclosure;

FIG. 7 is a sequence diagram illustrating interactions between basestations and interactions between a base station and a user equipment ina case that a wireless communication device according to an embodimentof the present disclosure is implemented as a base station;

FIG. 8 is a flowchart illustrating a process of a wireless communicationmethod according to another embodiment of the present disclosure;

FIG. 9 is a block diagram illustrating a functional configuration of awireless communication device according to another embodiment of thepresent disclosure;

FIG. 10 is a sequence diagram illustrating a data transfer between auser equipment and a base station and a data transfer between a basestation and a manager in a case that a wireless communication deviceaccording to an embodiment of the present disclosure is implemented asthe manager; and

FIG. 11 is a sequence diagram illustrating an implementation of a powerallocating solution according to the present disclosure in a wirelesscommunication network.

DETAILED DESCRIPTION OF EMBODIMENTS

In the following, embodiments of the present disclosure are described inconjunction with the drawings. It should be noted that, for clarity,representations and descriptions of parts and processes, which areindependent of the present disclosure and known by those skilled in theart, are omitted in the drawings and the descriptions.

A high efficient power control solution is provided by the presentdisclosure, for a scenario of different-frequency deployment of smallcell, so as to improve a system throughput. Specifically, in anembodiment, with a wireless communication device and a wirelesscommunication method according to the present disclosure, transmissionpower is determined in a corresponding manner based on an overallchannel quality of downlinks of a cell on which a transmission powercontrol is to be performed (also referred to as “target cell”hereinafter) in a cell cluster and other cells (also referred to as“non-target cell” hereinafter) in the cell cluster on a specificresource block.

FIG. 1 is a block diagram illustrating a functional configuration of awireless communication device 100 according to an embodiment of thepresent disclosure. The wireless communication device 100 may bearranged independently as a controller controlling transmission power ofall cells in a cell cluster, or arranged in each of cells in the cellcluster, or arranged in a specified cell.

The wireless communication device 100 includes a classification unit 101and a control unit 102. The classification unit 101 is configured toclassify, based on channel qualities of downlinks of a target cell andother cells in a cell cluster on a specific resource block, an overallchannel quality. For example, the classification unit 101 may classifythe overall channel quality as good, normal, bad. The channel quality ofthe downlinks of respective cells in the cell cluster on the specificresource block may be characterized with any conventional indicators orparameters in the art. And the overall channel quality may be classifiedaccording to a predetermined classification criterion, for example, bycomparing these indicators or parameters with thresholds predeterminedbased on practical experiences. In the present disclosure, for example,the channel quality may be characterized with signal to interferenceplus noise ratios (SINRs) fed back by user equipments (UE) which occupythe specific resource block and are within coverage ranges of therespective cells.

It is assumed that in a certain network scenario, a cell clusterincludes N cells SC_(n) (n=1, 2, . . . , N). S resource blocks (RBs) areshared by the cells in the cell cluster and an RB of one cell can onlybe occupied by one user equipment. A user equipment served by a targetcell CS_(i) and scheduled on a resource block k is represented withUE_(i) ^(k), and the SINR of UE_(i) ^(k) is represented with γ_(i) ^(k).Similarly, a user equipment served by a non-target cell CS_(j) (j=1, 2,. . . , N and j≠i) and scheduled on the resource block k is representedwith UE_(j) ^(k), and the SINR of UE_(j) ^(k) is represented with γ_(j)^(k). Then the classification unit 101 may be configured to: classify anoverall channel quality of downlinks of the cell cluster on the resourceblock k as good in a case that γ_(i) ^(k) and γ_(j) ^(k) are both muchgreater than 1(>>1); classify the overall channel quality of thedownlinks of the cell cluster on the resource block k as bad in a casethat γ_(i) ^(k) and γ_(j) ^(k) are both much less than 1(<<1); andclassify the overall channel quality as normal in other cases.

In an embodiment, the classification unit 101 may classify the overallchannel quality based on predetermined thresholds. For example, forpre-stored thresholds Th1=0.5 and Th2=5, the classification unit 101 maybe configured to: classify the overall channel quality of the downlinksof the cell cluster on the resource block k as good in a case that γ_(i)^(k)>5 and γ_(j) ^(k)>5, where it is considered that γ_(i) ^(k) andγ_(j) ^(k) are both much greater than 1; classify the overall channelquality as bad in a case that γ_(i) ^(k)<0.5 and γ_(j) ^(k)<0.5, whereit is considered that γ_(i) ^(k) and γ_(j) ^(k) are both much less than1; and classify the overall channel quality as normal in other cases.

The control unit 102 performs a control to determine transmission powerp_(i) ^(k) by a power allocating method adaptive to a classificationdetermined by the classification unit 101, as a target transmissionpower of the target cell CS_(i) on the specific resource block k. Inview of different system requirements such as a requirement ofmaximizing a system throughput or a requirement of ensuring an accuratereception of a signal transferred under a bad channel quality, thecontrol unit 102 may be configured to determine the target transmissionpower of the target cell CS_(i) on the specific resource block k bydifferent power allocating methods. For example, in a case that it needsto be ensured that user equipments can reliably receive downlink signalsunder a bad overall channel quality of downlinks of cells in a cellcluster on a certain resource block, the control unit 102 may beconfigured to determine power allocations for the target cell onrespective resource blocks in such a way that power determined with apower determination method used for a resource block with channelquality of downlinks classified as “bad” is higher than that determinedwith a power determination method used for a resource block with channelquality of downlinks classified as “good”. The specific method may bedetermined by those skilled in the art as needed.

FIG. 2 is a flowchart illustrating a process of a wireless communicationmethod according to an embodiment of the present disclosure. In stepS201, based on channel qualities of downlinks of a target cell CS_(i)and other cells CS_(j) (j=1, 2, . . . , N and j≠i) in a cell cluster ona specific resource block k, an overall channel quality is classified bya wireless communication device 100 according to the present disclosure.For example, the wireless communication device 100 may classified theoverall channel quality based on acquired SINRs γ_(n) ^(k) (n=1, 2, . .. , N) fed back to a cell base station from user equipments UEs in thecell cluster which occupy the resource block k. The SINRs γ_(n) ^(k) maybe used to characterize the channel quality of the downlinks of therespective cells on the resource block k.

For example, in step S201, the overall channel quality may be classifiedas good, normal, bad. For example, the overall channel quality may bedetermined by determining the relations (“much greater”, “much less” andthe like) of SINRs of the target cell and other cells and 1. Whether itis “much greater” or “much less” may be determined with a predeterminedthreshold. The details thereof are omitted herein as they have alreadybeen described above.

In step S202, a control is performed such that a target transmissionpower of the target cell CS_(i) on the specific resource block k isdetermined by a power allocating method adaptive to the classificationof step S201. The Power allocating methods adaptive to differentclassifications may be designed based on system requirements, which havebeen described briefly above by examples. Hereinafter, an embodiment ofa power allocating solution designed for maximizing a system throughputis described in detail with reference to FIGS. 3 to 5.

FIG. 3 is a block diagram illustrating a functional configuration of awireless communication device 300 according to an embodiment of thepresent disclosure. The wireless communication 300 includes aclassification unit 301, a control unit 302 and a calculation unit 303.Functions and structures of the classification unit 301 are the same asthose of the classification unit 101 described in conjunction with FIG.1, which are not described in detail hereinafter.

The calculation unit 303 calculates inter-cell SINR of a target cellCS_(i) with regard to a respective non-target cell CS_(j) (j=1, 2, . . ., N and j≠i) on a specific resource block k, which is referred to as“inter-cell SINR” hereinafter. The inter-cell SINR is defined as a ratioof interference of the target cell on a certain non-target cell versus asum of all interference and noise the non-target cell is subjected to,on a certain resource block. An inter-cell SINR λ_(i,j) ^(k) of thetarget cell CS_(i) (a cell to be allocated with power) with regard to auser equipment UE_(j) ^(k) scheduled by the non-target cell (a cellother than the target cell) CS_(j) on the resource block k may berepresented with the following formula (1):

$\begin{matrix}{\lambda_{i,j}^{k} = \frac{p_{i}^{k}g_{i,j}^{k}}{{I\left( p_{- j}^{k} \right)} + \sigma^{2}}} & (1)\end{matrix}$

where p_(i) ^(k) represents the transmission power of the target cellCS_(i) on the resource block k, and g_(i,j) ^(k) represents a channelgain from the target cell CS_(i) to the user equipment UE_(j) ^(k) ofthe non-target cell CS_(j). Therefore, the numerator p_(i) ^(k) g_(i,j)^(k) represents the interference on the user equipment UE_(j) ^(k) by atransmission of the cell CS_(i), i.e. the received power of thetransmission of the cell CS_(i) at the user equipment UE_(j) ^(k), whichmay be obtained by the user equipment UE_(j) ^(k) via a measurement. Inaddition, I(p_(−j) ^(k)) represents the interference on the non-targetcell CS_(j) from all other cells in the cell cluster on the resourceblock k, and σ² represents all noises the non-target cell CS_(j) issubjected to. I(p_(−j) ^(k)) may be calculated according to thefollowing formula (2):

$\begin{matrix}{{I\left( p_{- j}^{k} \right)} = {\sum\limits_{{n \neq j},{n = 1}}^{N}{p_{n}^{k}g_{n,j}^{k}}}} & (2)\end{matrix}$

It can be seen that, I(p_(−j) ^(k)) is a sum of received powers oftransmissions of all the cells other than the non-target cell CS_(j) atthe user equipment UE_(j) ^(k), on the resource block k. Similarly, thereceived power may be obtained by the user equipment UE_(j) ^(k) via ameasurement.

In an actual implementation, the value of I(p_(−j) ^(k)) may not becalculated exactly. The denominator of formula (1) indicates a sum ofpower of interference and noises, i.e., useless power. Therefore, thedenominator can be obtained as long as the user equipment UE_(j) ^(k)reports its SINR and the received power of its serving base station.This manner is more simple and accurate than a calculation with formula(2).

After calculating the inter-cell SINR of the target cell CS_(i) withregard to each non-target cell CS_(j) on the resource block k, thecalculation unit 303 may further calculate a sum of the inter-cell SINRsof the target cell CS_(i) with regard to all of the non-target cellsCS_(j) (j=1, 2, . . . , N and j≠i). The sum may be represented as

$\sum\limits_{j \neq i}{\lambda_{i,j}^{k}.}$

And the calculated sum of the inter-cell SINRs,

${\sum\limits_{j \neq i}\lambda_{i,j}^{k}},$

may be used in the power allocating solution described below.

In order to maximize the system throughput, the control unit 302 isconfigured to perform a control to determine a target transmission powerof the target cell on the specific resource block by a power allocatingmethod adaptive to a classification made by the classification unit 301.

Specifically, the control unit 301 may be configured to determinewhether the sum of the inter-cell SINRs,

${\sum\limits_{j \neq i}\lambda_{i,j}^{k}},$

is less than 1, in a case that the overall channel quality is classifiedas good, for example, when γ_(i) ^(k) an γ_(j) ^(k) are both muchgreater than 1. If it is determined that the sum of the inter-cell SINRsis not less than 1, the target transmission power may be determined bydecreasing, by a certain step length, the transmission power of thetarget cell CS_(i) on the resource block k. In addition, in someembodiments, if it is determined by the control unit 302 that the sum ofthe inter-cell SINRs is less than 1, the target transmission power ofthe target cell CS_(i) on the resource block may be determined by makinga first-order partial derivative of a total throughput R^(k) of allcells in the cell cluster on the specific resource block k with respectto the transmission power p_(i) ^(k) of the target cell CS_(i) on theresource block k equal to 0.

In the following, description is to be made in conjunction with specificformulas. In the network scenario assumed in the above, the totalthroughput R^(k) of all of the cells in the cell cluster on the resourceblock k may be represented with, for example, formula (3):

$\begin{matrix}{R^{k} = {\sum\limits_{i = 1}^{N}{\log_{2}\left( {1 + \frac{p_{i}^{k}g_{i,i}^{k}}{{\sum\limits_{{j \neq i},{j = 1}}^{N}{p_{j}^{k}g_{j,i}^{k}}} + \sigma^{2}}} \right)}}} & (3)\end{matrix}$

where meanings of superscripts and subscripts of parameters are similarto those described in the above and thus are not described repeatedlyherein. In an embodiment in which a quality of downlinks is representedwith a SINR, first-order and second-order partial derivatives of R^(k)with respect to the transmission power p_(i) ^(k) may be representedwith formula (4) and formula (5):

$\begin{matrix}{{{\frac{\partial R^{k}}{\partial p_{i}^{k}} = {{{\frac{1}{1 + \gamma_{i}^{k}} \cdot \frac{g_{i,i}^{k}}{{I\left( p_{- i}^{k} \right)} + \sigma^{2}}} + {\sum\limits_{j \neq i}^{N}{\frac{1}{1 + \gamma_{j}^{k}}{\left( {- \frac{p_{j}^{k}g_{j,j}^{k}}{\left( {{I\left( p_{- j}^{k} \right)} + \sigma^{2}} \right)^{2}}} \right) \cdot g_{i,j}^{k}}}}} = {\frac{\gamma_{i}^{k}}{p_{i}^{k}\left( {1 + \gamma_{i}^{k}} \right)} - {\sum\limits_{j \neq i}^{N}\frac{{g_{i,j}^{k}\left( \gamma_{j}^{k} \right)}^{2}}{p_{j}^{k}{g_{j,j}^{k}\left( {1 + \gamma_{j}^{k}} \right)}}}}}},{p_{i}^{k} \neq 0}}{and}{p_{j}^{k} \neq 0}} & (4) \\{{{\frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}} = {{{\left\lbrack {{- \frac{1}{\left( {1 + \gamma_{i}^{k}} \right)^{2}}} \cdot \frac{g_{i,i}^{k}}{{I\left( p_{- i}^{k} \right)} + \sigma^{2}}} \right\rbrack \cdot \frac{g_{i,i}^{k}}{{I\left( p_{- i}^{k} \right)} + \sigma^{2}}} - {\sum\limits_{j \neq i}^{N}{\frac{g_{i,j}^{k}}{p_{j}^{k}g_{j,j}^{k}} \cdot {\frac{{2\; {\gamma_{j}^{k}\left( {1 + \gamma_{j}^{k}} \right)}} - \left( \gamma_{j}^{k} \right)^{2}}{\left( {1 + \gamma_{i}^{k}} \right)^{2}}\left\lbrack {- \frac{p_{j}^{k}g_{j,j}^{k}}{\left( {{I\left( p_{- j}^{k} \right)} + \sigma^{2}} \right)^{2}}} \right\rbrack} \cdot g_{i,j}^{k}}}} = {{- \frac{\left( \gamma_{i}^{k} \right)^{2}}{\left( p_{i}^{k} \right)^{2}\left( {1 + \gamma_{i}^{k}} \right)^{2}}} + {\sum\limits_{j \neq i}^{N}{\left( \frac{g_{i,j}^{k}}{p_{j}^{k}g_{j,j}^{k}} \right)^{2}\frac{\left( \gamma_{j}^{k} \right)^{4} + {2\left( \gamma_{j}^{k} \right)^{3}}}{\left( {1 + \gamma_{j}^{k}} \right)^{2}}}}}}},{p_{i}^{k} \neq 0}}{and}{p_{j}^{k} \neq 0}} & (5)\end{matrix}$

Formula (4) and formula (5) may be simplified in a case that the overallchannel quality is classified as good, i.e. γ_(i) ^(k) and γ_(j) ^(k),are both much greater than 1 (generally, γ_(i) ^(k) and γ_(j) ^(k) areboth much greater than 1 in a case that the overall channel quality ofthe downlinks is good). In addition, by substituting the inter-cell SINRλ_(i,j) ^(k), the first-order and second-order partial derivatives ofthe total throughput R^(k) with respect to p_(i) ^(k) may be convertedinto:

$\begin{matrix}{{\frac{\partial R^{k}}{\partial p_{i}^{k}} \approx {\frac{1}{P_{i}^{k}} - {\sum\limits_{j \neq i}^{N}\frac{g_{i,j}^{k}\gamma_{j}^{k}}{p_{j}^{k}g_{j,j}^{k}}}}} = \frac{1 - {\sum\limits_{j \neq i}^{N}\lambda_{i,j}^{k}}}{p_{i}^{k}}} & (6) \\{{\frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}} \approx {{- \frac{1}{\left( P_{i}^{k} \right)^{2}}} + {\sum\limits_{j \neq i}^{N}\left( \frac{g_{i,j}^{k}\gamma_{j}^{k}}{p_{j}^{k}g_{j,j}^{k}} \right)^{2}}}} = {{{- \frac{1}{\left( P_{i}^{k} \right)^{2}}} + {\sum\limits_{j \neq i}^{N}\left\lbrack \frac{g_{i,j}^{k}}{{I\left( p_{- j}^{k} \right)} + \sigma^{2}} \right\rbrack^{2}}} = \frac{{\sum\limits_{j \neq i}^{N}\left( \lambda_{i,j}^{k} \right)^{2}} - 1}{\left( P_{i}^{k} \right)^{2}}}} & (7)\end{matrix}$

With formulas (6) and (7), the variation characteristic of a totalthroughput of the network varying with the transmission power of thetarget cell may be obtained. FIG. 4 is a schematic diagram illustratingthe variation characteristic of the total throughput of the networkvarying with the transmission power of the target cell in a case thatγ_(i) ^(k) and γ_(j) ^(k) are both much greater than 1.

If the sum of the inter-cell SINRs,

${\sum\limits_{j \neq i}^{N}\lambda_{i,j}^{k}},$

is less than 1 (i.e.

$\left. {\frac{\partial R^{k}}{\partial p_{i}^{k}} > 0} \right),$

then λ_(i,j) ^(k)<1 for any values of j. Then

$\sum\limits_{j \neq i}^{N}\left( \lambda_{i,j}^{k} \right)^{2}$

is less than 1,

$\frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}} < 0.$

It can be seen that, R^(k)(p_(i) ^(k)) is a convex function, as shown in(a) of FIG. 4. Therefore, when

${\frac{\partial R^{k}}{\partial p_{i}^{k}} = 0},$

R^(k)(p_(i) ^(k)) has an optimum solution, which is represented by “P”.Otherwise, if the sum of inter-cell SINRs,

${\sum\limits_{j \neq i}^{N}\lambda_{i,j}^{k}},$

is not less than 1, then the function R^(k)(p_(i) ^(k)) is a concavefunction, as shown in (b) of FIG. 4, of which an optimum solution cannot obtained directly.

Similarly, in a case that the overall channel quality is classified asbad, for example, in a case that the channel quality is represented witha SINR and γ_(i) ^(k) and γ_(j) ^(k) are both much less than 1 (i.e.γ_(i) ^(k)<<1 and γ_(h) ^(k)<<1), it may be deduced that

$\frac{\partial R^{k}}{\partial p_{i}^{k}} > {0\mspace{14mu} {and}\mspace{14mu} \frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}}} < 0$

based on formulas (4) and (5). Therefore, an optimum solution ofR^(k)(p_(i) ^(k)) may also be obtained when

$\frac{\partial R^{k}}{\partial p_{i}^{k}} = 0.$

Therefore, the control unit 302 may be configured to perform a controlto, in a case that the overall channel quality is classified as bad,determine the target transmission power of the target cell CS_(i) on theresource block k by making the first-order partial derivative of thetotal throughput R^(k) of all of the cells in the cell cluster on theresource block k with respect to the transmission power p_(i) ^(k) ofthe target cell CS_(i) on the resource block k equal to 0.

In a case that the overall channel quality is normal, for example, in acase that when the channel quality are represented by γ_(i) ^(k) andγ_(j) ^(k), γ_(i) ^(k) and γ_(j) ^(k) are neither both much less than 1nor both much greater than 1, it is difficult to directly determine thevariation characteristic of R^(k)(p_(i) ^(k)) based on the SINRs γ_(i)^(k) and γ_(j) ^(k) and the sum of inter-cell SINRs,

$\sum\limits_{j \neq i}^{N}{\lambda_{i,j}^{k}.}$

Therefore, the variation characteristic of R^(k)(p_(i) ^(k)) may beobtained by directly calculating the first-order and second-orderpartial derivatives of R^(k) with respect to p_(i) ^(k) by, for example,formula (4) and formula (5), and comparing them with 0 respectively.

In an embodiment, the calculation unit 303 may have the followingfunction: compare values of the first-order and second-order partialderivatives of the total throughput R^(k) of all of the cells in thecluster on the resource block k with respect to the transmission powerp_(i) ^(k) of the target cell CS_(i) on the resource block k,

${\frac{\partial R^{k}}{\partial p_{i}^{k}}\mspace{14mu} {and}\mspace{14mu} \frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}}},$

with 0, and provide the comparison result to the control unit 302. Thecontrol unit 302 may be configured to perform a control to determine thetarget transmission power of the target cell CS_(i) on the resourceblock k by making the first-order partial derivative

${\frac{\partial R^{k}}{\partial p_{i}^{k}} = 0},$

in a case that the overall channel quality is classified as normal andit is determined by the calculation unit 303 via the comparison that thevalue of the first-order partial derivative

$\frac{\partial R^{k}}{\partial p_{i}^{k}}$

is greater than 0 and the value of the second-order partial derivative

$\frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}}$

is less than 0. In addition, the control unit 302 may be furtherconfigured to perform a control to determine the target transmissionpower by decreasing, by a certain step length, the transmission power ofthe target cell CS_(i) on the resource block k, in a case that theoverall channel quality is classified as normal and it is determined bythe calculation unit 303 via the comparison that the value of thefirst-order partial derivative

$\frac{\partial R^{k}}{\partial p_{i}^{k}}$

is less than 0.

In the following, taking an embodiment of integrating (implementing) thewireless communication device 300 into (as) a cell base station as anexample, a data transfer between a user equipment and a cell basestation in a wireless communication system using a power allocatingsolution according to the present disclosure is described in conjunctionwith FIG. 5.

FIG. 5 is a sequence diagram illustrating a data transfer between a userequipment and a cell base station in a case that the wirelesscommunication device 300 according to the embodiment of the presentdisclosure is integrated into the cell base station.

It can be seen from the above analysis that, the wireless communicationdevice 300 needs to acquire the following contents to select a properpower allocating solution: SINRs γ_(n) ^(k) (n=1, 2, . . . , N) of thecells in the cell cluster on the resource block k, and inter-cell SINRsλ_(i,j) ^(k) (referred to as “inter-cell SINR” hereinafter) of thetarget cell CS_(i) with respect to all of the other cells CS_(j) (j=1,2, . . . , N and j≠i) on the resource block k.

Here, the SINR γ_(n) ^(k) may be obtained by feeding back from userequipments to their serving cells and interactions between cells. Forexample, in FIG. 5, user equipments UE_(i) ^(k) in the target cellscheduled on the resource block k and UE_(j) ^(k) in other cellsscheduled on the resource block k measure SINRs of their serving cellson the resource block k, γ_(i) ^(k) and γ_(j) ^(k), and feedback γ_(i)^(k) and γ_(j) ^(k) to base stations of their serving cells. In theembodiment, the non-target cell CS_(j) provides its SINR γ) to thetarget cell CS_(i). Then, the wireless communication device 300 includedin the base station of the target cell CS_(i) may classify an overallchannel quality of downlinks on the resource block k.

In addition, it can be seen from definition formulas (1) and (2) ofinter-cell SINR λ_(i,j) ^(k) that, interferences on the cell CS_(j) byall cells other than the cell CS_(j) on the resource block k, i.e.received power p_(m,j) ^(k) (m=1, 2, . . . , N and m≠j) received by theuser equipment UE_(j) ^(k) respectively from all the cells other thanthe cell CS_(j), p_(m,j) ^(k)=p_(m) ^(k)g_(m,j) ^(k), needs to beacquired to calculate λ_(i,j) ^(k). In FIG. 5, the user equipment UE_(j)^(k) measures p_(m,j) ^(k) and delivers p_(m,j) ^(k) to a base stationof the cell CS_(j). Then, the inter-cell SINR λ_(i,j) ^(k) may becalculated in the base station of the cell CS_(j) according to formulas(1) and (2) using all of received power p_(m,j) ^(k) (m=1, 2, . . . , Nand m≠j) received. Then, the cell CS_(j) provides λ_(i,j) ^(k) to thecell CS_(i), for the wireless communication device 300 included in thebase station of the target cell CS_(i) to calculate the sum ofinter-cell SINRs,

$\sum\limits_{j \neq i}^{N}{\lambda_{i,j}^{k}.}$

In a case that the overall channel quality is classified as normal, itis needed to compare respectively, with zero, the values of thefirst-order and second-order partial derivatives of the total throughputR^(k) of all the cells in the cell cluster on the resource block k withrespect to the transmission power p_(i) ^(k) of the target cell CS_(i)on the resource block k,

$\frac{\partial R^{k}}{\partial p_{i}^{k}}\mspace{14mu} {and}\mspace{14mu} {\frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}}.}$

Therefore, it can be seen from formulas (4) and (5) that, the wirelesscommunication device 300 needs to further obtain channel gains g_(i,j)^(k), g_(i,i) ^(k), and g_(j,j) ^(k). It can be appreciated by thoseskilled in the art that these gains may be obtained in various knownmanners, for example, by calculating a ratio of transmission powerversus corresponding received power.

After obtaining sufficient data, the wireless communication device 300included in the target cell CS_(i) may determine a target transmissionpower with a corresponding method. In a case that the method in whichthe first-order derivative

$\frac{\partial R^{k}}{\partial p_{i}^{k}} = 0$

is adopted to determine the target transmission power, the followingdeduced formula (8) may be adopted:

$\begin{matrix}\begin{matrix}{\frac{\partial R^{k}}{\partial p_{i}^{k}} = {{\frac{1}{1 + \gamma_{i}^{k}} \cdot \frac{g_{i,i}^{k}}{{I\left( p_{- i}^{k} \right)} + \sigma^{2}}} +}} \\{{\sum\limits_{j \neq i}^{N}{\frac{1}{1 + \gamma_{j}^{k}}{\left( {- \frac{p_{j}^{k}g_{j,j}^{k}}{\left( {{I\left( p_{- j}^{k} \right)} + \sigma^{2}} \right)^{2}}} \right) \cdot g_{i,j}^{k}}}}} \\{= {{{\frac{\gamma_{i}^{k}}{1 + \gamma_{i}^{k}} \cdot \frac{1}{p_{i}^{k}}} - {\frac{1}{p_{i}^{k}}{\sum\limits_{j \neq i}^{N}{\frac{\gamma_{j}^{k}}{1 + \gamma_{j}^{k}} \cdot \lambda_{i,j}^{k}}}}} = 0}} \\{{\left. \Rightarrow\frac{\gamma_{i}^{k}}{1 + \gamma_{i}^{k}} \right. = {\sum\limits_{j \neq i}^{N}{\frac{\gamma_{j}^{k}}{1 + \gamma_{j}^{k}} \cdot \lambda_{i,j}^{k}}}}} \\{{{\left. \Rightarrow p_{i}^{k} \right. = \frac{A}{H\left( {1 - A} \right)}},}} \\{{{{{where}\mspace{14mu} A} = {\sum\limits_{j \neq i}^{N}{\frac{\gamma_{j}^{k}}{1 + \gamma_{j}^{k}} \cdot \lambda_{i,j}^{k}}}},{H = \frac{g_{i,i}^{k}}{{I\left( p_{- i}^{k} \right)} + \sigma^{2}}}}}\end{matrix} & (8)\end{matrix}$

where meanings of symbols are the same as or similar to those describedin the above, and thus are not described herein.

It should be noted that, the timing sequence of measuring, feeding backand providing related parameters and the timing sequence of operationsof classification, calculation and determination, etc., shown in FIG. 5are only examples without intending to limit the present disclosure, andcan be adjusted in any ways as needed. In addition, a subject performingthe operations such as classification, calculation and determination maybe changed as needed. For example, the inter-cell SINR may be directlycalculated by the user equipment or may be all calculated in the basestation of the target cell.

With the wireless communication device and the wireless communicationmethod corresponding to the operations performed by the wirelesscommunication device described above, a target transmission power of atarget cell on a specific resource block may be determined by a powerallocating method adaptive to a classification of an overall channelquality of downlinks on the specific resource block, thereby maximizinga system throughput of a wireless network on the specific resource blockin a dense small cell deployment.

In the following, another embodiment according to the present disclosureis described in conjunction with FIGS. 6 to 10. FIG. 6 is a blockdiagram illustrating a functional configuration of a wirelesscommunication device 600 according to an embodiment of the presentdisclosure. The wireless communication device 600 includes aclassification unit 601, an allocating unit 602 and a control unit 603.

The classification unit 601 is configured to classify a user equipmentUE (classifying the user equipment into different types) based onaverage channel quality of downlinks to the user equipment UE in a cellcluster in a predetermined time period. The average channel quality ofthe user equipment UE in the predetermined time period may be acquiredby using any type of data capable of indicating the channel quality ofthe downlink. The average channel quality of the downlink to the userequipment UE in the predetermined time period may be characterized by,for example, but not limited to, an average SINR of the user equipmentUE in the predetermined time period.

FIG. 7 is a sequence diagram illustrating an interaction between a basestation and a user equipment and an interaction between the base stationand the wireless communication device 600 (manager) in a case that thewireless communication device 600 according to the embodiment of thepresent disclosure is arranged separately from the base station (inother words, implemented as a manager of the cell cluster). A cell CSrepresents each of the cells in a cell cluster, and UE represents a userequipment served by the cell CS. The user equipment UE measures a SINR γwhich can characterize the quality of downlinks to the user equipmentUE, and feeds γ back to a base station of its serving cell. The basestation may calculate an average value γ of SINRs received in thepredetermined time period and provide the obtained average value to amanager. Alternatively, the base station may directly provide the SINRsfed back from the user equipment to the manager, and the managercalculates the average value of the SINRs centrally. Then, the managermay classify the user equipment based on the calculated average value.

In an example, the classification unit 601 may be configured to:classify the user equipment into a first type (also referred to as atype of “good” hereinafter) in a case that the average SINR is muchgreater than 1; classify the user equipment into a second type (alsoreferred to as a type of “bad” hereinafter) in a case that the averageSINR is much less than 1; and classify the user equipment into a thirdtype (also referred to as a type of “normal” hereinafter) in a case thatthe average SINR is neither much greater than nor much less than 1.

In a specific implementation, predetermined threshold Th3 and Th4(Th3<Th4) may be set previously. If the average SINR γ>Th4, it isconsidered that γ>>1 and the user equipment is determined to be in thefirst type. If γ<Th3, it is considered that γ<<1 and the user equipmentis determined to be in the second type. If Th3≤γ≤Th4, it is consideredthat γ is neither much greater than nor much less than 1, and the userequipment is determined to be in the third type. For example, Th3 andTh4 may have the same values as Th1 and Th2 respectively. For example,Th3=0.5 and Th4=5.

In an example, if a cell cluster includes totally 12 user equipments UE1to UE12, and Th3=1 and Th4=10, then classification results of the userequipments are as shown in Table 1:

TABLE 1 USER EQUIPMENT γ TYPE UE1 0.4 bad UE2 0.3 bad UE3 5 normal UE411 good UE5 0.8 bad UE6 4.2 normal UE7 10.8 good UE8 0.6 bad UE9 3.5normal UE10 4.6 normal UE11 7.8 normal UE12 13.4 good

After the classification unit 601 classifies the user equipment UE basedon the average channel quality in the predetermined time period, theallocating unit 602 may allocate a resource block set to the userequipment at least partly based on the type of the user equipment. Inthe embodiment, the allocating unit 602 may allocate a same resourceblock set for user equipments of the same classification. For example,in a case of totally having 50 resource blocks, as shown in FIG. 2, userequipments of the type of “bad” may be allocated with resource blocksRB1 to RB 10, user equipments of the type of “normal” may be allocatedwith resource blocks RB15 to RB40, and user equipments of the type of“good” may be allocated with resource blocks RB41 to RB50.

TABLE 2 Type of user equipment RB BAD RB1~RB10 NORMAL RB15~RB40 GOODRB41~RB50

Table 2 shows an example of a resource block set allocation to the userequipments. In a specific implementation, the resource block set may beallocated to user equipments of the same type based on differentrequirements and using different criterions. For example, the allocatingunit 602 may be configured to allocate a resource block set to a userequipment at least partly based on the numbers of user equipments ofdifferent types. Besides, for example, the allocating unit 602 may befurther configured to allocate a resource block set at least partlybased on service requirements of the user equipments of different types.

As shown in FIG. 7, in addition to the average value of the SINRs, thebase station may further provide information such as servicerequirements of the user equipments to the manager. After classifyingthe user equipments, the manager may allocate resource block sets to theuser equipments of different types by combining information such as thetypes of the user equipments, the numbers of the user equipments ofdifferent types, and the service requirements of the user equipments ofdifferent types. Then, the manager informs the base stations of thecells of an allocating result of resource block sets.

Upon receiving the allocating results of resource block set, the basestation schedules user equipments of a corresponding type on a resourceblock based on the allocating result. In this way, the user equipment UEcommunicates on the allocated resource block.

It should be noted that, the timing sequence of measuring, feeding backand providing related parameters and the timing sequence of operationssuch as classification, calculation and determination shown in FIG. 7are only examples without intending to limit the present disclosure, andcan be adjusted in any ways as needed. In addition, a subject performingthe operations such as classification, calculation and determination maybe changed as needed.

The control unit 603 is configured to perform a control to determine atarget transmission power of the target cell on the specific resourceblock by a power allocating method adaptive to a classification of auser equipment UE_(i) ^(k) scheduled by the target cell CS_(i) (a cellon which a power control is to be performed) on the specific resourceblock k.

In view of different system requirements such as a requirement ofmaximizing a system throughput or a requirement of ensuring an accuratereception of a signal transferred under a bad channel quality, thecontrol unit 603 may be configured to determine the target transmissionpower of the target cell CS_(i) on the specific resource block k bydifferent power allocating methods. For example, in a case that a userequipment even classified as the type of “bad” needs to be ensured toreceive a downlink signal reliably, the control unit 603 may beconfigured to determine power of the target cell on the resource blocksallocated to user equipments of different types in such a way that thepower determined with a power determination method for a resource blockoccupied by user equipments of the type of “bad” is higher than thepower determined with a power determination method for a resource blockoccupied by user equipments of the type of “good”. The specific methodmay be determined by those skilled in the art as needed.

FIG. 8 is a flowchart illustrating a process of a wireless communicationmethod according to an embodiment of the present disclosure. In stepS801, a user equipment is classified based on average channel quality ofdownlinks to the user equipment in a cell cluster in a predeterminedtime period. In step S802, a resource block set is allocated to the userequipment at least partly based on a classification of the userequipment, wherein a same resource block set is allocated to userequipments of the same classification. And in step S803, a control isperformed to determine a target transmission power of the target cell onthe specific resource block by a power allocating method adaptive to aclassification of the user equipment scheduled by the target cell on thespecific resource block. The details of the respective steps have beendescribed in conjunction with the wireless communication device 600above, and thus are not described herein.

FIG. 9 is a block diagram illustrating a functional configuration of awireless communication device 900 according to an embodiment of thepresent disclosure. The wireless communication device 900 includes: aclassification unit 901, an allocating unit 902, a control unit 903 anda calculation unit 904. Functions and structures of the classificationunit 901 and the allocating unit 902 are the same as those of theclassification 601 and the allocating unit 602 described in conjunctionwith FIG. 6, and thus are not described in detail hereinafter.

The calculation unit 904 calculates inter-cell SINRs of the target cellCS_(i) with respect to each non-target cell CS_(j) (j=1, 2, . . . , Nand j≠i) on a specific resource block k, which is referred to as“inter-cell SINR” hereinafter. Inter-cell SINR is defined as a ratio ofinterference of the target cell on a certain non-target cell versus asum of all interference and noise the non-target cell is subjected to,on a certain resource block. An inter-cell SINR λ_(i,j) ^(k) of thetarget cell CS_(i) to the user equipment UE_(j) ^(k) scheduled by thenon-target cell CS_(j) on the resource block k may be represented withthe above formula (1), and thus is not described repeatedly herein. Theinter-cell SINR λ_(i,j) ^(k) may be calculated based on received powerat the user equipment UE_(j) ^(k) from a transmission of the cellCS_(i), which is obtained by the user equipment UE_(j) ^(k) via ameasurement, and a sum of received power on the user equipment UE_(j)^(k) from transmissions of each of cells other than the non-target cellCS_(j) on the resource block k, which is obtained by the user equipmentUE_(j) ^(k) via a measurement.

After calculating the inter-cell SINR of the target cell CS_(i) withrespect to each non-target cell CS_(j) on the resource block k, thecalculation unit 904 may further calculate a sum of the inter-cell SINRsof the target cell CS_(i) with respect to all of the non-target cellsCS_(j) (j=1, 2, . . . , N and j≠i). The sum may be represented as

$\sum\limits_{j \neq i}^{\;}{\lambda_{i,j}^{k}.}$

The calculated sum of the inter-cell SINRs,

${\sum\limits_{j \neq i}^{\;}\lambda_{i,j}^{k}},$

may be used in a power allocating solution described below.

The control unit 903 may be configured, based on the object ofmaximizing a system throughput, to perform a control to determinewhether the sum of the inter-cell SINRs,

${\sum\limits_{j \neq i}^{\;}\lambda_{i,j}^{k}},$

is less than 1 in a case that the user equipment UE_(i) ^(k) is of thetype of good (“the first type”); and determine a target transmissionpower by decreasing, by a certain step length, the transmission powerp_(i) ^(k) of the target cell CS_(i) on the resource block k if it isdetermined that the sum of the inter-cell SINRs,

${\sum\limits_{j \neq i}^{\;}\lambda_{i,j}^{k}},$

is not less than 1; or determine a target transmission power of thetarget cell CS_(i) on the specific resource block by making afirst-order partial derivative of a total throughput R^(k) of cells inthe cell cluster on the resource block k with respect to thetransmission power p_(i) ^(k) of the target cell CS_(i) on the specificresource block k equal to 0, if it is determined that the sum of theinter-cell SINRs,

${\sum\limits_{j \neq i}^{\;}\lambda_{i,j}^{k}},$

is less than 1.

Actually, the wireless communication device 900 corresponds to thewireless communication device 300 described above in conjunction withthe FIG. 3 in that: the wireless communication device 300 selects aproper power determination method based on a classification (forexample, by comparing γ_(i) ^(k) and γ_(j) ^(k) respectively with 1) ofan overall channel quality; while the wireless communication device 900classifies the user equipment based on a channel quality of downlinks ona whole frequency band, then allocates a same resource block set to userequipments of the same classification, and selects a proper powerdetermination method based on the classifications of the userequipments. Actually, the user equipment classification and resourceblock allocating performed by the latter wireless communication deviceensures, in a probability as high as possible, that downlinks to theuser equipments scheduled by different serving cells on the sameresource block have similar quality. That is to say, in a case that thequality of the downlink is characterized with a SINR, the user equipmentclassification and resource block allocating performed by the latterwireless communication device ensure, in a probability as high aspossible, that a comparison result between γ_(i) ^(k) and 1 is the sameas a comparison result between γ_(i) ^(k) and 1 (for example, γ_(i) ^(k)and γ_(j) ^(k) are both much greater than 1, or both much less than 1).

Therefore, in an embodiment, the control unit 903 may also be configuredto perform a control to determine the target transmission power of thetarget cell CS_(i) on the resource block k by making the first-orderpartial derivative of the total throughput R^(k) of all the cells in thecell cluster on the resource block k with respect to the transmissionpower p_(i) ^(k) of the target cell CS_(i) on the specific resourceblock k equal to 0, in a case that the user equipment is of the type of“bad” (“the second type”), that is, in a high probability, γ_(i) ^(k) ofthe user equipment UE_(i) ^(k) and γ_(j) ^(k) of a user equipment UE_(j)^(k) scheduled on the same resource block k as the user equipment UE_(i)^(k) are both much less than 1.

If the user equipment UE_(i) ^(k) is of the type of “normal” (“the thirdtype”), it can be seen that, in a high probability, the quality ofdownlinks to the user equipment and the quality of downlinks to a userequipment UE_(j) ^(k) scheduled on the same resource block k as the userequipment UE_(i) ^(k) are both normal. For example, the SINRs γ_(i) ^(k)and γ_(j) ^(k) may both be neither much greater than 1 nor much lessthan 1. In this case, similar to the wireless communication device 300,the calculation unit 904 of the wireless communication device 900 may beconfigured to compare values of first-order and second-order partialderivatives of the total throughput R^(k) of all of the cells in thecell cluster on the resource block k with respect to the transmissionpower p_(i) ^(k) of the target cell CS_(i) on the resource k with zero.And the control unit 903 may be configured to determine the targettransmission power of the target cell CS_(i) on the resource block k bymaking the first-order partial derivative equal to 0, in a case that theuser equipment is of the type of “normal” (“the third type”) and it isdetermined by the calculation unit 904 via the comparison that the valueof the first-order partial derivative is greater than 0 and the value ofthe second-order partial derivative is less than 0.

Alternatively, the control unit 903 may be configured to determine atarget transmission power by decreasing, by a certain step length,transmission power of a target cell on a specific resource block in acase that the user equipment is of the type of “normal” (“the thirdtype”) and it is determined by the calculation unit 904 via thecomparison that the value of the first-order partial derivative is lessthan 0.

In the following, still taking the embodiment in which the wirelesscommunication device 900 is implemented as a network manager as anexample, a data transfers between a user equipment and a cell basestation and between a cell base station and the manager, in a wirelesscommunication system using the power allocating solution according tothe present disclosure are described in conjunction with FIG. 10.

FIG. 10 is a sequence diagram illustrating data transfers between a userequipment and a base station and between a base station and a manager ina case that the wireless communication device 900 is implemented as amanager according to the embodiment of the present disclosure. Transfersand operations shown in FIG. 10 are performed following the resourceblock allocating operation shown in FIG. 7. In other words, as comparedwith FIG. 7, user equipments in FIG. 10 have been scheduled on specificresource blocks (k) adaptive to types of the user equipments.

The embodiment shown in FIG. 10 differs from the embodiment shown inFIG. 5 in that: in the embodiment shown in FIG. 10, it is unnecessary todetermine an overall downlinks since types of the user equipments havebeen determined; in addition, the operations of calculating theinter-cell SINR λ_(i,j) ^(k), the sum of inter-cell SINRs,

${\sum\limits_{j \neq i}^{N\;}\lambda_{i,j}^{k}},$

and various gains (such as g_(i,j) ^(k), g_(i,i) ^(k), and g_(j,j) ^(k))are all done at the manager. And the operation of determining the targettransmission power of the target cell CS_(i) is done at the manager.Then, the target cell CS_(i) is informed of the determined targettransmission power.

Due to these differences, the data transfer is changed accordingly. Forexample, after a user equipment UE_(j) ^(k) of a non-target cell CSdelivers to the cell CS_(j) the measured received power p_(m,j) ^(k)(m=1, 2, . . . , N and m≠j) which are received from all cells other thanthe cell CS_(j), the cell CS_(j) provides the received power to themanager for calculating by the manager the sum of inter-cell SINRs,

${\sum\limits_{j \neq i}^{N\;}\lambda_{i,j}^{k}},$

and various gains.

The operation of “determining the power” performed in the managergenerally includes: all operations in the above control unit 903, andthe operations in the calculation unit 904 of calculating the values ofthe first-order partial derivative

$\frac{\partial R^{k}}{\partial p_{i}^{k}}$

and the second-order partial derivative

$\frac{\partial^{2}R^{k}}{\partial\left( p_{i}^{k} \right)^{2}},$

comparing the values of the first-order and second-order partialderivatives with zero, and the like.

It should be noted that, the timing sequence of measuring, feeding backand providing related parameters and the timing sequence of operationssuch as calculation and determination shown in FIG. 10 are only exampleswithout intending to limit the present disclosure, and can be adjustedin any ways as needed. In addition, in a case that the wirelesscommunication device 900 is implemented as a base station (beingincluded in a base station), similar data transmission is made between auser equipment and the base station and between base stations.

FIG. 11 is a sequence diagram illustrating an implementation of a powerallocating solution according to the present disclosure in a wirelesscommunication network. As shown in FIG. 11, in a time period ofimplementing the solution, the power allocating solution according tothe present disclosure, a state determination and a power allocating areperformed based on information acquired in preceding time, andsubsequently, the information acquisition, state determination and powerallocating are performed iteratively.

With the wireless communication devices and the wireless communicationmethod corresponding to the operations performed by the wirelesscommunication devices described above, a user equipment may beclassified based on average quality of downlinks in a predetermined timeperiod, and a same resource block set is provided to user equipments ofthe same classification in a cell cluster. Then, a target transmissionpower of the target cell on a specific resource block is determined by apower allocating method adaptive to the type of the user equipment,thereby maximizing a system throughput of a wireless network on thespecific resource block under a dense small cell deployment.

Furthermore, a computer program may be created, which enable hardware(such as Central Processing Unit (CPU), a Read-Only Memory (ROM) and aRandom Access Memory (RAM)) mounted in a base station, a communicationterminal or a network manager to perform functions equivalent to thoseof parts of the base station, the communication terminal or the networkmanager. In addition, a storage medium storing the computer program isalso provided.

In the above description of the embodiments of the present disclosure, afeature described and/or shown for an embodiment may be used in one ormore other embodiments in a same or similar manner, and may be combinedwith a feature of another embodiments or replace a feature of anotherembodiment.

It should be noted that, the term “include/contain”, when used in thepresent disclosure, is to specify the presence of a feature, an element,a step or a component, but do not exclude the presence or addition ofone or more other features, elements, steps or components.

In addition, the method according to the present disclosure is notlimited to be performed in the time order described in the description,and may be performed sequentially, in parallel or independently in othertime orders. Therefore, the technical scope of the present disclosure isnot limited to the performing order of the method described in thespecification.

In the above, the present disclosure is disclosed with the descriptionsof the embodiments thereof. However, it should be understood that,various modifications, improvements or equivalents thereof may bedesigned for the present disclosure by those skilled in the art withinthe spirit and scope of the appended claims. These modifications,improvements or equivalents thereof should be considered to fall withinthe protection scope of the present disclosure.

The following embodiments are further described in the presentdisclosure:

1. A wireless communication device, including:

a classification unit, configured to classify, based on channelqualities of downlinks of a target cell and other cells in a cellcluster on a specific resource block, an overall channel quality; and

a control unit, configured to perform a control to determine a targettransmission power of the target cell on the specific resource block bya power allocating method adaptive to a classification of the overallchannel quality.

2. The wireless communication device according to embodiment 1, whereinaccording to a predetermined classification criterion, theclassification of the overall channel quality includes: good, normal,and bad.

3. The wireless communication device according to embodiment 2, whereineach of the channel qualities is characterized by a SINR.

4. The wireless communication device according to embodiment 3, whereinthe predetermined classification criterion includes:

the overall channel quality is classified as good in a case that SINRsof the target cell and the other cells are all much greater than 1;

the overall channel quality is classified as bad in a case that SINRs ofthe target cell and the other cells are all much less than 1; and

the overall channel quality is classified as normal in other cases.

5. The wireless communication device according to any one of embodiments1-4, further including a calculation unit, wherein the calculation unitis configured to calculate an inter-cell SINR of the target cell withrespect to a first other cell on the specific resource block, and theinter-cell SINR is defined as: a ratio of the interference on the firstother cell from the target cell versus a sum of all interference andnoise the first other cell is subjected to, on the specific resourceblock.

6. The wireless communication device according to embodiment 5, whereinthe calculation unit is further configured to calculate a sum ofinter-cell SINRs of the target cell with respect to all of the othercells in the cell cluster on the specific resource block.

7. The wireless communication device according to embodiment 6, whereinthe control unit is configured to performed the control to determinewhether the sum of the inter-cell SINRs is less than 1 if the overallchannel quality is classified as good, and determine the targettransmission power by decreasing, by a certain step length, transmissionpower of the target cell on the specific resource block if it isdetermined that the sum of the inter-cell SINRs is not less than 1.

8. The wireless communication device according to embodiment 6 or 7,wherein the control unit is configured to perform a control to determinewhether the sum of the inter-cell SINRs is less than 1 if the overallchannel quality is classified as good; and determine the targettransmission power of the target cell on the specific resource block bymaking a first-order partial derivative of a total throughput of allcells in the cell cluster on the specific resource block with respect tothe transmission power of the target cell on the specific resource blockequal to 0 if it is determined that the sum of the inter-cell SINRs isless than 1.

9. The wireless communication device according to any one of embodiments2-8, wherein the control unit is configured to perform a control todetermine the target transmission power of the target cell on thespecific resource block by making a first-order partial derivative of atotal throughput of all cells in the cell cluster on the specificresource block with respect to the transmission power of the target cellon the specific resource block equal to 0 if the overall channel qualityis classified as bad.

10. The wireless communication device according to any one ofembodiments 2-9, wherein the calculation unit is further configured tocompare values of first-order and second-order partial derivatives of atotal throughput of all cells in the cell cluster on the specificresource block with respect to the transmission power of the target cellon the specific resource block with zero; and

the control unit is configured to perform a control to determine thetarget transmission power of the target cell on the specific resourceblock by making the first-order partial derivative equal to 0, in a casethat the overall channel quality is classified as normal and it isdetermined by the calculation unit via the comparison that the value ofthe first-order partial derivative is greater than 0 and the value ofthe second-order partial derivative is less than 0.

11. The wireless communication device according to embodiment 10,wherein the control unit is configured to perform a control to determinethe target transmission power of the target cell on the specificresource block by decreasing, by a certain step length, the transmissionpower of the target cell on the specific resource block, in a case thatthe overall channel quality is classified as normal and it is determinedby the calculation unit via the comparison that the value of thefirst-order partial derivative is less than 0.

12. The wireless communication device according to any one ofembodiments 8-11, wherein the first-order partial derivative isrepresented as

$\frac{\partial R^{k}}{\partial p_{i}^{k}},$

wherein

$R^{k} = {\sum\limits_{i = 1}^{N}{\log_{2}\left( {1 + \frac{p_{i}^{k}g_{i,i}^{k}}{{\sum\limits_{{j \neq i},{j = 1}}^{N}{p_{j}^{k}g_{j,i}^{k}}} + \sigma^{2}}} \right)}}$

represents th total throughput of all the cells in the cell cluster onthe specific resource block k, p_(i) ^(k) represents the transmissionpower of a cell CS_(i) on the resource block k, g_(i,j) ^(k) representsa channel gain from a cell CS_(j) to a user equipment in the cell CS_(i)occupying the resource block k, σ² represents power of white Gaussiannoise.

13. A wireless communication method, including:

classifying an overall channel quality based on channel qualities ofdownlinks of a target cell and other cells in a cell cluster on aspecific resource block; and

perform a control to determine a target transmission power of the targetcell on the specific resource block by a power allocating methodadaptive to a classification of the overall condition.

14. The wireless communication method according to embodiment 13,wherein according to a predetermined classification criterion, theclassification of the overall channel quality includes: good, normal,and bad.

15. The wireless communication method according to embodiment 14,wherein each of the channel qualities is characterized by a SINR.

16. The wireless communication method according to embodiment 15,wherein the predetermined classification criterion includes:

the overall channel quality is classified as good if SINRs of the targetcell and the other cells are all much greater than 1;

the overall channel quality is classified as bad if SINRs of the targetcell and the other cells are all much less than 1; and

the overall channel quality is classified as normal in other cases.

17. The wireless communication method according to any one ofembodiments 13-16, further including: calculating an inter-cell SINR ofthe target cell with respect to a first other cell on the specificresource block, wherein the inter-cell SINR is defined as: a ratio ofthe interference on the first other cell from the target cell versus asum of all interference and noise the first other cell is subjected to,on the specific resource block.

18. The wireless communication method according to embodiment 17,further including: calculating a sum of inter-cell SINRs of the targetcell with respect to all of other cells in the cell cluster on thespecific resource block.

19. The wireless communication method according to embodiment 18,wherein the controlling includes: determining whether the sum of theinter-cell SINRs is less than 1 in a case that the overall channelquality is classified as good; and determining the target transmissionpower by decreasing, by a certain step length, transmission power of thetarget cell on the specific resource block, if it is determined that thesum of the inter-cell SINRs is not less than 1.

20. The wireless communication method according to embodiment 18 or 19,wherein the controlling includes: determining whether the sum of theinter-cell SINRs is less than 1 in a case that the overall channelquality is classified as good; and determining the target transmissionpower of the target cell on the specific resource block by making afirst-order partial derivative of a total throughput of all cells in thecell cluster on the specific resource block with respect to thetransmission power of the target cell on the specific resource blockequal to 0, if it is determined that the sum of the inter-cell SINRs isless than 1.

21. The wireless communication method according to any one ofembodiments 14-20, wherein the controlling includes: determining thetarget transmission power of the target cell on the specific resourceblock by making a first-order partial derivative of a total throughputof all cells in the cell cluster on the specific resource block withrespect to transmission power of the target cell on the specificresource block equal to 0, in a case that the overall channel quality isclassified as bad.

22. The wireless communication method according to any one ofembodiments 14-21, further including: comparing values of first-orderand second-order partial derivatives of a total throughput of all cellsin the cell cluster on the specific resource block with respect totransmission power of the target cell on the specific resource blockwith 0; and

the controlling includes: determining the target transmission power ofthe target cell on the specific resource block by making the first-orderpartial derivative equal to 0, in a case that the overall channelquality is classified as normal and it is determined via the comparisonthat the value of the first-order partial derivative is greater than 0and the value of the second-order partial derivative is less than 0.

23. The wireless communication method according to embodiment 22,wherein the controlling includes: determining the target transmissionpower of the target cell on the specific resource block by decreasing,by a certain step length, the transmission power of the target cell onthe specific resource block, in a case that the overall channel qualityis classified as normal and it is determined by the comparison that thevalue of the first-order partial derivative is less than 0.

24. The wireless communication method according to any one ofembodiments 20-23, wherein the first-order partial derivative isrepresented as

$\frac{\partial R^{k}}{\partial p_{i}^{k}},$

wherein

$R^{k} = {\sum\limits_{i = 1}^{N}{\log_{2}\left( {1 + \frac{p_{i}^{k}g_{i,i}^{k}}{{\sum\limits_{{j \neq i},{j = 1}}^{N}{p_{j}^{k}g_{j,i}^{k}}} + \sigma^{2}}} \right)}}$

represents the total throughput of all the cells in the cell cluster ona specific resource block k, p_(i) ^(k) represents the transmissionpower of a cell CS_(i) on the resource block k, g_(i,j) ^(k) representsa channel gain from a cell CS_(j) to a user equipment in the cell CS_(i)occupying the resource block k, and σ² presents power of white Gaussiannoise.

25. A wireless communication device, including:

a classification unit, configured to classify a user equipment in a cellcluster based on average channel quality of downlinks to the userequipment in a predetermined time period;

an allocating unit, configured to allocate a resource block set to theuser equipment at least partly based on the classification of the userequipment, wherein the allocating unit allocates a same resource blockset to user equipments of the same classification; and

a control unit, configured to perform a control to determine a targettransmission power of a target cell on a specific resource block by apower allocating method adaptive to a classification of the userequipment scheduled by the target cell on the specific resource block.

26. The wireless communication device according to embodiment 25,wherein the average channel quality is characterized by an average SINRof the user equipment in the predetermined time period.

27. The wireless communication device according to embodiment 26,wherein the classification unit is configured to: classify the userequipment into a first type if the average SINR is much greater than 1;

classify the user equipment into a second type if the average SINR ismuch less than 1; and

classify the user equipment into a third type if the average SINR isneither much greater than 1 nor much less than 1.

28. The wireless communication device according to any one ofembodiments 25 to 27, wherein the allocating unit allocates the resourceblock set to the user equipment at least partly based on the numbers ofuser equipments of different types.

29. The wireless communication device according to embodiment 28,wherein the allocating unit allocates the resource block set at leastpartly based on service requirements of the user equipments of differentclassifications.

30. The wireless communication device according to embodiment 29,further including: a calculation unit, wherein the calculation unit isconfigured to calculate an inter-cell SINR of the target cell withrespect to a first non-target cell on the specific resource block,wherein the inter-cell SINR is defined as: a ratio of the interferenceon the first non-target cell from the target cell versus a sum of allinterference and noise the first non-target cell is subjected to, on thespecific resource block.

31. The wireless communication device according to embodiment 30,wherein the calculation unit is further configured to calculate a sum ofinter-cell SINRs of the target cell with respect to all non-target cellsin the cell cluster.

32. The wireless communication device according to embodiment 31,wherein the control unit is configured to: determine whether the sum ofthe inter-cell SINRs is less than 1 in a case that the user equipment isclassified into the first type; and determine the target transmissionpower of the target cell on the specific resource block by making afirst-order partial derivative of a total throughput of all cells in thecell cluster on the specific resource block with respect to transmissionpower of the target cell on the specific resource block equal to 0, ifit is determined that the sum of the inter-cell SINRs is less than 1.

33. The wireless communication device according to embodiment 31 or 32,wherein the control unit is configured to: determine whether the sum ofthe inter-cell 1 SINRs is less than 1 in a case that the user equipmentis classified into the first type; and determine the target transmissionpower by decreasing, by a certain step length, transmission power of thetarget cell on the specific resource block, if the sum of the inter-cellsignal to interference plus noise is not less than 1.

34. The wireless communication device according to any one ofembodiments 27 to 33, wherein the control unit is configured to:determine the target transmission power of the target cell on thespecific resource block by making a first-order partial derivative of atotal throughput of all cells in the cell cluster on the specificresource block with respect to the transmission power of the target cellon the specific resource block equal to 0, if the user equipment isclassified into the second type.

35. The wireless communication device according to any one ofembodiments 27 to 34, wherein the calculation unit is further configuredto compare values of first-order and second-order partial derivatives ofa total throughput of all cells in the cell cluster on the specificresource block with respect to the transmission power of the target cellon the specific resource block with 0; and

the control unit is configured to determine the target transmissionpower of the target cell on the specific resource block by making thefirst-order partial derivative equal to 0, in a case that the userequipment is classified into the third type and it is determined by thecalculation unit via the comparison that the value of the first-orderpartial derivative is greater than 0 and the value of the second-orderpartial derivative is less than 0.

36. The wireless communication device according to embodiment 35,wherein the control unit is configured to determine the targettransmission power of the target cell on the specific resource block bydecreasing, by a certain step length, the transmission power of thetarget cell on the specific resource block, in a case that the userequipment is classified into the third type and it is determined by thecalculation unit via the comparison that the value of the first-orderpartial derivative is less than 0.

37. A wireless communication method, including:

classifying a user equipment in a cell cluster based on average channelquality of downlinks to the user equipment in a predetermined timeperiod;

allocating a resource block set to the user equipment at least partlybased on a classification of the user equipment, wherein a same resourceblock set is allocated to user equipments of the same classification;and

performing a control to determine a target transmission power of atarget cell on a specific resource block by a power allocating methodadaptive to a classification of the user equipment scheduled by thetarget cell on the specific resource block.

38. The wireless communication method according to embodiment 37,wherein the average channel quality is characterized by an average SINRof the user equipment in the predetermined time period.

39. The wireless communication method according to embodiment 38,wherein the classifying includes:

classifying the user equipment into a first type if the average SINR ismuch greater than 1;

classifying the user equipment into a second type if the average SINR ismuch less than 1; and

classifying the user equipment into a third type if the average SINR isneither much greater than 1 nor much less than 1.

40. The wireless communication method according to any one ofembodiments 37 to 39, wherein the resource block set is allocated to theuser equipment at least partly based on the numbers of user equipmentsof different types.

41. The wireless communication method according to embodiment 40,wherein the resource block set is allocated at least partly based onservice requirements of the user equipments of different types.

42. The wireless communication method according to embodiment 41,further including: calculating an inter-cell SINR of the target cellwith respect to a first non-target cell on the specific resource block,wherein the inter-cell SINR is defined as: a ratio of the interferenceon the first non-target cell from the target cell versus a sum of allinterference and noise the first non-target cell is subjected to, on thespecific resource block.

43. The wireless communication method according to embodiment 42,further including: calculating a sum of inter-cell SINRs of the targetcell with respect to all of non-target cells in the cell cluster.

44. The wireless communication method according to embodiment 43,wherein the controlling includes: determining whether the sum of theinter-cell SINRs is less than 1 in a case that the user equipment isclassified into the first type; and determining the target transmissionpower of the target cell on the specific resource block by making afirst-order partial derivative of a total throughput of all cells in thecell cluster on the specific resource block with respect to transmissionpower of the target cell on the specific resource block equal to 0, ifit is determined that the sum of the inter-cell SINRs is less than 1.

45. The wireless communication method according to embodiment 43 or 44,wherein the controlling includes: determining whether the sum of theinter-cell SINRs is less than 1 in a case that the user equipment isclassified into the first type; and determining the target transmissionpower by decreasing, by a certain step length, transmission power of thetarget cell on the specific resource block, if it is determined that thesum of the inter-cell signal to interference plus noise is not less than1.

46. The wireless communication method according to any one ofembodiments 39 to 45, wherein the controlling includes: determining thetarget transmission power of the target cell on the specific resourceblock by making a first-order partial derivative of a total throughputof all cells in the cell cluster on the specific resource block withrespect to transmission power of the target cell on the specificresource block equal to 0, if the user equipment is classified into thesecond type.

47. The wireless communication method according to any one ofembodiments 39 to 46, further including: comparing values of first-orderand second-order partial derivatives of a total throughput of all cellsin the cell cluster on the specific resource block with respect totransmission power of the target cell on the specific resource blockwith 0; and

the controlling includes: determining the target transmission power ofthe target cell on the specific resource block by making the first-orderpartial derivative equal to 0, in a case that the user equipment isclassified into the third type and it is determined via the comparisonthat the value of the first-order partial derivative is greater than 0and the value of the second-order partial derivative is less than 0.

48. The wireless communication method according to embodiment 47,wherein the controlling includes: determining the target transmissionpower of the target cell on the specific resource block by decreasing,by a certain step length, transmission power of the target cell on thespecific resource block, in a case that the user equipment is classifiedinto the third type and it is determined via the comparison that thevalue of the first-order partial derivative is less than 0.

49. A wireless communication system, including the wirelesscommunication device according to any one of embodiments 1-12 andembodiments 25-36.

50. The wireless communication system according to embodiment 49,wherein the wireless communication device is arranged in a base stationof the wireless communication system, or is arranged separately from thebase station.

51. The wireless communication system according to embodiment 50,wherein a user equipment in the wireless communication system measuresand provides received power received by the user equipment from allcells other than a serving cell of the user equipment.

1. A wireless communication device, comprising: circuitry configured toclassify an overall channel quality based on the channel qualities ofdownlinks, on a specific resource block, of a target cell and othercells in a cell cluster; and control a target transmission power, on thespecific resource block, of the target cell using the classification ofthe overall channel quality so that the target cell operates with thetarget transmission power.
 2. The wireless communication device of claim1, wherein according to a predetermined classification criterion, theclassification of the overall channel quality comprises at least one ofa first classification (good), a second classification (normal), and athird classification (bad).
 3. The wireless communication device ofclaim 2, wherein each of the channel qualities is characterized by asignal to interference plus noise ratio (SINR).
 4. The wirelesscommunication device of claim 3, wherein the predeterminedclassification criterion comprises: the overall channel quality isclassified as the first classification (good) if SINRs of the targetcell and the other cells are greater than a threshold value by a firstpredetermined amount; the overall channel quality is classified as thethird classification if SINRs of the target cell and the other cells areless than a threshold value by a predetermined amount; and the overallchannel quality is classified as the second classification in othercases.
 5. The wireless communication device of claim 1, wherein thecircuitry is configured to calculate an inter-cell SINR of the targetcell with respect to a first other cell on the specific resource block.6. The wireless communication device of claim 5, wherein the inter-cellSINR is defined as: a ratio of the interference on the first other cellfrom the target cell versus a sum of all interference and noise thefirst other cell is subjected to, on the specific resource block.
 7. Thewireless communication device of claim 6, wherein the circuitry isconfigured to calculate a sum of inter-cell SINRs of the target cellwith respect to all of other cells in the cell cluster on the specificresource block.
 8. The wireless communication device of claim 7, whereinthe circuitry is configured to control so as to: determine the targettransmission power by decreasing, by a certain step length, transmissionpower of the target cell on the specific resource block if it isdetermined that the sum of the inter-cell SINRs is greater than
 1. 9. Awireless communication method, comprising: classifying, using circuitry,an overall channel quality based on the channel qualities of downlinks,on a specific resource block, of a target cell and other cells in a cellcluster; and controlling a target transmission power, on the specificresource block, of the target cell using the classification of theoverall channel quality so that the target cell operates with the targettransmission power.
 10. A wireless communication device, comprising:circuitry configured to classify a user equipment in a cell clusterbased on average channel quality of downlinks to the user equipment in apredetermined time period; allocate a resource block set to the userequipment at least partly based on a classification of the userequipment, wherein the resource block set is allocated to userequipments of the same classification; and control a target transmissionpower of a target cell on a specific resource block using theclassification of the user equipment scheduled by the target cell on thespecific resource block so that the target cell operates with the targettransmission power.
 11. The wireless communication device of claim 10,wherein the average channel quality is characterized by an average SINRof the user equipment in the predetermined time period.
 12. The wirelesscommunication device of claim 11, wherein the circuitry is furtherconfigured to: classify the user equipment into a first type if theaverage SINR is greater than a threshold value by a first predeterminedamount; classify the user equipment into a second type if the averageSINR is less than the threshold value by a second predetermined amount;and classify the user equipment into a third type if it is notclassified as the first type or the second type.
 13. The wirelesscommunication device of claim 10, wherein the circuitry is configured toallocate the resource block set to the user equipment at least partlybased on the numbers of user equipments of different types.
 14. Thewireless communication device of claim 13, wherein the circuitry isconfigured to allocate the resource block set at least partly based onservice requirements of the user equipments of different types.
 15. Thewireless communication device of claim 13, wherein the circuitry isconfigured to calculate an inter-cell SINR of the target cell withrespect to a first non-target cell on the specific resource block,wherein the inter-cell SINR is defined as: a ratio of the interferenceon the first non-target cell from the target cell versus a sum of allinterference and noise the first non-target cell is subjected to, on thespecific resource block.
 16. The wireless communication device of claim15, wherein the circuitry is configured to calculate a sum of inter-cellSINRs of the target cell with respect to all of non-target cells in thecell cluster on the specific resource block.
 17. The wirelesscommunication device of claim 16, wherein the circuitry is configuredto: determine whether the sum of the inter-cell SINRs is less than 1 ifthe user equipment is of the first type; and determine the targettransmission power of the target cell on the specific resource block, bymaking a first-order partial derivative of a total throughput of allcells in the cell cluster on the specific resource block with respect totransmission power of the target cell on the specific resource blockequal to 0, if it is determined that the sum of the inter-cell SINRs isless than
 1. 18. The wireless communication device of claim 16, whereinthe circuitry is configured to: determine whether the sum of theinter-cell SINRs is less than 1 if the user equipment is of the firsttype; and determine the target transmission power by decreasing, by acertain step length, transmission power of the target cell on thespecific resource block, if it is determined that the sum of theinter-cell SINRs is not less than
 1. 19. The wireless communicationdevice of claim 12, wherein the circuitry is configured to determine thetarget transmission power of the target cell on the specific resourceblock by making a first-order partial derivative of a total throughputof all cells in the cell cluster on the specific resource block withrespect to transmission power of the target cell on the specificresource block equal to 0, if the user equipment is of the second type.20. The wireless communication device of claim 12, wherein the circuitryis configured to: respectively compare values of first-order andsecond-order partial derivatives of a total throughput of all cells inthe cell cluster on the specific resource block with respect totransmission power of the target cell on the specific resource blockwith 0; and determine the target transmission power of the target cellon the specific resource block by making the first-order partialderivative equal to 0, in a case that the user equipment is of the thirdtype and it is determined by the calculation unit via the comparisonthat the value of the first-order partial derivative is greater than 0and the value of the second-order partial derivative is less than 0.